The present invention relates to a high-voltage measurement device for use in an electrical high-voltage switchboard plant with an encapsulating housing. The high voltage measurement device includes a measurement electrode which extends into the encapsulating housing and an electrical conductor which conducts a measurement signal provided by the measurement electrode. The electrical conductor is connected with the measurement electrode and passes through the wall of the encapsulating housing in an insulated manner.
Such a measurement device is known, for example, from the technical article. Albiez, et al., "DESIGN AND CALIBRATION OF A UNIVERSAL SENSOR FOR THE MEASUREMENT OF PARTIAL DISCHARGES AND VERY FAST TRANSIENTS IN GIS", SIXTH INTERNATIONAL SYMPOSIUM ON HIGH VOLTAGE ENGINEEERING, New Orleans, La., USA, (Aug. 28-Sep. 1, 1989). In the Albiez article. for example, a measurement sensor is represented in FIG. 5, from which a conductor passes to the outside through the wall of an encapsulating housing, in insulated manner. The measurement sensor discussed in the Albiez article is used for several purposes, namely for measuring partial discharges and for measuring fast transients, with a matching external circuit in each instance.
A high-voltage measurement device for an electrical high-voltage switchboard plant with an encapsulating housing and a measurement electrode built into the latter, as well as an electrical conductor which conducts a measurement signal, connected with the electrode and passed through the wall of the encapsulating housing in insulated manner is known from the German patent publication number DE-PS 34 09 016 ("'the 016 publication").
In the 016 publication, the measurement electrode is formed by a contact spring which can be connected with the phases of bus conductors by means of a contact blade.
In normal operation of the switchboard plant described in the '016 publication, the contact spring is open so that high voltage can be capacitatively coupled out of the switching system via the conductor. The high voltage is then applied at the conductor on the outside of the encapsulating housing, and could endanger the operating personnel under certain circumstances. Only in the grounded state of the grounding switch is the contact spring, and thus also the conductor which passes through the wall of the encapsulating housing, grounded and therefore accessible without danger.